It is well known that factors in the pregnant woman's environment can adversely affect the fetus. Organ and limb malformations, poor growth, and brain injury manifesting in developmental delay and learning disabilities are some of the problems that have been attributed to prenatal exposures to teratogenic agents. This article describes two intensively studied prenatal teratogen exposures in the pregnant woman— anticonvulsant medications and alcohol. In the fetus, both exposures can produce poor growth and miscarriages; in the newborn, poor growth, small head size, and major and minor malformations are seen. Infants and young children with histories of such intrauterine exposure may be mentally retarded and have significant social and behavioral problems. Many of the anatomic and behavioral problems observed in children who were exposed to alcohol and anticonvulsant medications have been replicated in prenatally exposed laboratory animals. Parents and professionals can benefit from awareness of disability related to fetal exposure; training in this area can both improve early identification of affected children and aid in prevention of exposure-related impairments. Parents and professionals should also be cognizant of these problems for their own reproductive health.